The maintenance period for my only MBX database AND only PF database is scheduled to take place between 11 PM and 3 AM (23:00 and 3:00). My MBX database is not quite 9 GB in size. My PF database is a massive 6 MB in size (just needed for BESX). At 2:02, there's a 1221 Event ID in the App log: "The database "First Storage Group\Mailbox Database" has 142 megabytes of free space after online defragmentation has terminated. " At 2:15, we have a 700 Event ID in the App log: MSExchangeIS (3420) First Storage Group: Online defragmentation is beginning a full pass on database 'E:\EXDB\Mailbox Database.edb'. So online defrag starts again (???). At 2:59 we have a 704 Event ID: " MSExchangeIS (3420) First Storage Group: Online defragmentation of database 'E:\EXDB\Mailbox Database.edb' was interrupted and terminated. The next time online defragmentation is started on this database, it will resume from the point of interruption. " This is followed by a 9871 warning: "There is an online maintenance overlap for database "First Storage Group\Mailbox Database". Please revise the online maintenance schedule. " Why is the online defrag starting again at 2:15 AM when it supposedly finished at 2:02? A full backup of both databases is performed at 4:30 AM. Should I perhaps increase the maintenance period to 4:00 AM so it finishes? But still... is that restart of online defragmentation normal???

If it's finishing during the period at least once, you're fine. The schedule is a collection of 15-minute blocks, which is why it restarted at 0215. It's not a big deal that it restarts and gets interrupted. Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

From the way I've always understood it Exchange will perform multiple passes of online defrags if the allotted window time allows for it (someone correct me if I"m wrong.) Thus you need to reduce the window. The guidance from MS has been to at least OLD run a complete pass at least 1-2 weeks, though this is not a hard recommendation since every config\org is has different needs ie. backup window, performance issues etc. After 2007 SP1, perfmon counters have been added to calculate how often OLD should run based your own environment and it's churning of pages of data in the database. Exchange 2007 SP1 ESE Changes - Part 2 http://blogs.technet.com/b/exchange/archive/2007/12/06/3404504.aspx James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

You may want to consider using a software solution that defrags while your machines are running so you don't have to worry about maintenance times, etc. I have spoken to hundreds of IT Managers several of whom run sites with over 1,000 workstations and dozens of servers and they swear by automatic, transparent programs that defrag on demand with no impact on system resources. Here is some info on this type of set up: http://downloads.diskeeper.com/pdf/The-Impact-Of-Disk-Fragmentation-On-Servers.pdf Check it out and get a free trial so you can see what it can do for your site.

That doesn't replace Exchange's online store maintenance and is generally considered unnecessary for an Exchange server.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."